This invention relates to a method for dyeing a hydrophobic fiber. More particularly, it relates to a method for dyeing a hydrophobic fiber in particular, a polyester fiber in an extremely brilliant yellow or orange with various excellent fastnesses and fluorescence by using a coumarin compound. The present invention further relates to a method for coloring organic macromolecular substances applicable to, for example, the raw materials of various electric and electronic parts and automotive parts and to a coloring material usable in these macromolecular substances, colored toners for electrophotography and fluorescent pigments.
In recent years, consumers' growing interest in leisure and choice of high-grade goods present an ever-increasing demand for sports wear with brilliant colors. In particular, there has been urgently required to develop a dye, which is capable of giving a brilliant color and excellent in various fastnesses for dyeing polyester fibers or blends of polyester fibers with other fibers.
And recently, there appears an ultra fine polyester microfiber as a novel synthetic fiber. This so-called microfiber has a tendency to show a low apparent depth of shade compared with a regular fiber which has been dyed with the same dye at the same color concentration. In order to dye the microfiber so as to give the same depth of shade, therefore, it is required to use a large amount of a dye compared with the case of dyeing a regular fiber. As a result, it is sometimes observed that various fastnesses is deteriorated thereby. Thus it is furthermore strongly required to develop a disperse dye which is excellent in various fastnesses, in particular, lightfastness and wetfastness and gives an extremely brilliant color.
Meanwhile, to color synthetic macromolecular substances in yellow, there have been used oil-soluble dyes such as anthraquinone dyes, quinophthalone dyes and perinone dyes and organic pigments such as anthraquinone pigments, isoindolinone pigments and quinophthalone pigments.
The present inventors have conducted extensive studies in order to develop a dye whereby polyester fibers or blends of polyester fibers with other fibers can be dyed with excellent dyeing affinity and a dyed fiber being excellent in various fastnesses and having an extremely brilliant color can be provided.
In the field of the coloration of organic macromolecular substances, each of the above-mentioned coloring agents has both advantages and disadvantages in tinctorial power, saturation and various fastnesses. Although it has been required to develop a coloring material with a more brilliant color in recent years, none of the known coloring agents can provide a satisfactory brightness. Hence, the present inventors have conducted intensive studies from this point of view too.